watchOS 4.2.2 (build 15S5540a) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm), released on 2018-01-09T18:13:34Z. The update package is 77.09 MB. This is a delta (partial) update that requires 4.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 2e8b417cb67cbbe239cd1bb8862ad5b806a8b617.zip.